JavaScript function to Validate Email

function validateEmail(address){
var flag=true;
if(address==""){
//** field is blank
flag=false;
} else{
var objRegExp  = /^[a-z0-9]([a-z0-9_\-\.]*)@([a-z0-9_\-\.]*)(\.[a-z]{2,3}(\.[a-z]{2}){0,2})$/i;
var emaildomain=new Array("com","net","org","edu","in","mil","gov","arpa","biz","aero","name","coop","info","pro","museum");
var suffix =address.substring(address.lastIndexOf('.')+1);
if(emaildomain.indexOf(suffix) != -1){
flag=true;
} else{ flag=false; }

if(objRegExp.test(address) == false) {
flag=false;
}
if (address.indexOf('@.',0) != -1) {
flag=false;
}
if (address.indexOf('.@',0) != -1) {
flag=false;
}
if (address.indexOf('..',0) != -1) {
flag=false;
}
}
return flag;
}